In present-day livestock management gastrointestinal metabolism disorders occur frequently, because their feeding had to be changed on account of the requirements of modern animal husbandry to ensure sufficient maintenance as well as growth of the animal mass for meat production and, moreover, sufficient production of products such as milk. It proves to be problematic here, among other things, that the resorption capacity of the gastrointestinal organs does not keep up with the demand.
The standard ration of a ruminant is green fodder in the form of grasses and cellulolytic byproducts from agricultural production. These are either fed fresh as pasture grass or cutting grass, in a dry form as hay or in a preserved state as silage. The ability to use these materials as food sources is only possible on account of a pre-gastric bacterial fermentation in the rumen, the section of the animal stomach that is not fundus-like. Here, a bacterial effect reduces the carbohydrates with a complex structure, cellulose, hemicellulose and lignin and the associated non-structure carbohydrates, pectin, starches and sugars to short-chain fatty acids, which are resorbed via the rumen wall and enter into the carbohydrate metabolism. Apart from the fatty acids nitrogen derivatives such as ammonia and electrolytes such as sodium, calcium and magnesium are also resorbed via the rumen wall and absorbed into the blood.
The microorganisms growing in the rumen are subjected to digestive action in the fundus-like stomach and small intestine after the efflux from the rumen and constitute the essential source of protein of the ruminant, whereas proteins contained in the feed are degraded by the microbial flora of the rumen predominantly to ammonia, which has to re-enter into the microbial protein biosynthesis in order to be utilized by the animal.
The adaptation of ruminants to a pre-gastric digestion has developed a system of retaining the ration that was taken in, which constitutes a significant part of the mechanism for the maximum extraction of energy from hard-to-digest structural carbohydrates. This retention requires a certain abstinence when taking in food, which is further restricted in foods that are based on green fodder, since the coarser ingested food needs to be retained longer in order to achieve an effective extraction of energy. This constitutes a special problem in modern domesticated ruminants, as the demand for nutrients created by a genetic selection with regard to a more rapid lean muscle growth or high levels of milk production to a great extent exceeds the supply formed by a fermentation of the ration based on green fodder.
The ration that has to be fed requires the addition of large amounts of non-structure carbohydrates (starches and sugars), which are fed in the form of grains. Furthermore, a supplementary feeding of nutrients rich in protein (e.g. soybean meal or legumes) is necessary to meet the demand for proteins. These additives lead to an accelerated fermentation activity in the rumen, wherein high concentrations of short-chain fatty acids and ammonia are released, which often constitute a source of physiological and metabolic stress. In particular, this often leads to an acidotic crisis of the rumen environment (rumen acidosis). As a consequence, feeding strategies must try to maximize the use of green fodder without negatively affecting the delivery of nutrients necessary for maintenance and production. Alternatively, one can try to optimize the resorption of the fermentation products produced in the rumen fermentation so that less or no gastrointestinal disorders, such as e.g. the rumen acidosis, occur.
Recommended treatments for rumen acidosis, as one of the most common gastrointestinal disorders or illnesses include the administration of a mixture of sodium bicarbonate, formaldehyde, magnesium oxide and carbon in order to kill the rapidly dividing bacteria (NebGuide G91-1047-A). However, the degradation of structural fibers from green fodder, hay or silage by bacterial enzymes, which is necessary for the further passage, is hereby also inhibited. To neutralize the acids produced during fermentation buffers are widely used (Horn, 1979, Kennelly, 1999), but do not appear to be effective enough to satisfy the animal industry. The palatability of most buffers is low and requires careful handling in order to avoid reduced feed intake. Ionophore antibiotics such as monensin, lasalocid and salinomycin are generally effective against gram-positive bacteria, including the main ruminal lactate-forming bacteria, S. bovis and species of lactobacillus (Burrin and Britton, 1986, Coe, 1999, Nagaraja, 1985). Hence, they are effective in preventing acute acidosis during the transition to high-concentrate feeding when cattle first arrive at the feedlots or after calving and stabilize the rumen pH. However, ionophores also reduce the feed intake. It has also been shown that other classes of antibiotics prevent or improve acute acidosis, including virginiamycin in sheep (Thorniley et al., 1998) and the sulfur-containing peptide antibiotic thiopeptin, which is especially effective against S. bovis (Armstrong, 1984). However, the continuous use of antibiotic feed additives is no longer viewed as a suitable management instrument due to, among other things, the development of resistance with consequent effects for humans (for an overview see: The use of drugs in food animals: benefits and risks, 1999).
In a further frequently occurring gastrointestinal disorder or disease, parturient paresis, the blood calcium level drops to values that lead to malfunctions in the neuromuscular stimulus conduction followed by paralysis. Causes are the high losses of calcium with the milk, the insufficient resorption capacity of the gastrointestinal tract and the insufficient mobilization from the body's reserves (bones and plasma proteins). The alkalotic metabolism status of the ruminant contributes to this. As therapy, usually differentiated feed is administered prior to and after calving, wherein mineral feed without calcium is administered in the dry period and mineral feed rich in calcium is administered beginning with the birth. Alternatively, high doses of calcium salts and vitamin D are administered. However, high doses of vitamin D can lead to irreversible calcifications of the soft tissue (Littledike et al., 1986) and the differential feeding is costly to carry out. Furthermore, vitamin D encourages the integration of calcium in the bone, which may result in a further drop in the blood calcium levels. When high concentrations of calcium salts are administered, this indeed leads to a partial correction of the alkalotic metabolism status of the animal with the ensuing ability to increasingly mobilize calcium from the bone (Goff and Horst, 1993), however, this is often accompanied by a decreased calcium absorption if the supplementary feeding lasts too long. Calcium doses that are too high can herein even be toxic (Goff et al., 2002). Furthermore, so-called “anionic” or “acidic” salts such as e.g. ammonium sulfate are employed (Goff et al. 2004; Gelfert et al. 2010), with which the alkalotic metabolism status of the ruminant is to be corrected in order to encourage the mobilization of calcium from bones and plasma proteins. However, a reduction of feed intake must also be reckoned with here. The parturient paresis still constitutes a considerable yield-reducing complication, and there is a demand for new feed supplements or means to prevent and alleviate the disease here also.
Based on this background, it was the object of the present invention to provide feed supplements which as feed supplement or as an integral component of a feed are suited to guarantee an optimal utilization of feeds in animals from the suborder of the ruminants (Ruminantia) or the (ruminant) tylopods (Tylopoda) by obviating the development of metabolically induced subclinical disorders or manifest diseases, such as e.g. rumen acidosis or parturient paresis, increase the protein utilization and/or improve the ingestion/performance ratio of the animal (e.g. milk production).